<!DOCTYPE html>
<html>
<body>
  <div role="section" id="container">
    <p>Text</p>
  </div>
<script>
  function go() {
    var region = document.createElement('div');
    region.setAttribute('aria-live', 'polite');
    document.getElementById('container').appendChild(region);
  }
</script>
</body>
</html>
